Timer

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//=========================================================================
// 工程名称： Demo_2440_timer
// 组成文件： timer.c
// 功能描述：实现0.5S的定时输出信息,练习定时器的使用
// 硬件连接：无
//=========================================================================

#include "2440addr.h"
#include "uart.h"
#include "2440lib.h"

void Timer_init(void);
void __irq timer0Handler(void);

int Main(void)
{
int i = 0,j=0;
memcpy(0x0,(unsigned char *)0x30000000,0x1000); //拷贝程序到0地址

ChangeMPllValue(0x5c,1,1); //FCLK = 400M
ChangeClockDivider(14,12); //HCLK = 100M , PCLK = 50M

Uart_Select(0);
myUart_Init(50000000,115200);

Uart_Printf("Timer Test\n");
Timer_init();

rTCON &= ~(0x0f<<0); //寄存器清0
rTCON |= (0x09<<0); //启动定时器
while(1);

}

void Timer_init(void)
{

rTCFG0 &= ~(0xff<<0); //寄存器清0
rTCFG0 |= (0x63<<0); //prescaler0 100 timer0的时钟频率为50M/100 = 0.5MHz

rTCFG1 &= ~(0x0f<<0); //寄存器清0
rTCFG1 |= (0x01<<0); //divide value 1/4 timer0的时钟频率为50M/100/4 = 0.5MHz/4 = 125KHz

rTCNTB0 = 62500; //设置Timer初值 n=f*t=125K × 0.5s = 62500;

rTCON &= ~(0x0f<<0); //寄存器清0 ，以一个定时器的控制位为单位进行设置
rTCON |= (0x02<<0); //自动重载, 反向关闭,手运装载初值 ,暂不启动(第一次启动前先得手运装载一次初值)

pISR_TIMER0=(unsigned)timer0Handler; //建立中断向量表
EnableIrq(BIT_TIMER0);
}

void __irq timer0Handler(void)
{
static int cont_num = 0;
cont_num++;
Uart_Printf("timer0 test cont: %d\n",cont_num);

ClearPending(BIT_TIMER0);
}